Question: When was Uber's total revenue equal to 6.5e+09?
Paraphrase: 6.5e+09 was total revenue of Uber during what time?
SPARQL (Wikidata): SELECT ?value WHERE { wd:Q780442 p:P2139 ?s . ?s ps:P2139 ?x filter(contains(?x , '6.5e+09')) . ?s pq:P585 ?value}